high photoluminescence efficiency and stability of quantum dot(QD)/polymer composite is necessary to QD LED. However, conventional Cd-based QD has toxic problem which has limitation in industrious application. So, it is necessary to fabricate Cd-free QD LED. And when QDs are incorporated in polymer matrix, aggregation of QDs occurs, reducing photoluminescence and stability of QD/polymer composite. on the other hands, high refractive index silicone encapsulant polymer is widely used instead of other organic polymers because of its light extraction efficiency and thermal stability. So, we investigated the change in various properties of QDs in phenyl hybrid silicone resin with QD dispersion control. We synthesized Cd-free CIS/ZnS QDs by cation exchange method and incorporated QDs within thiol functionalized silicone resin by direct sol-gel condensation reaction. 3-mercaptopropyl trimethoxysilane was chosen for silicone resin precursor because its methoxy group can react sol-gel condensation and thiol group has high enthalpic attractive force with metallic nanoparticles such as QDs. And through hydrosilylation reaction, we could fabricate cured QD/silicone nancomposites. Various properties of QD/silicone composite were measured by confocal microscopy, UV, PL, and integrating sphere. Optical properties such as QY, transmittance were increased when QDs were incorporated in thiol modified silicone resin becuase of higher dispersion state of QDs. And UV, thermal stability were also enhanced because of increase of polymer-particle intercation which prevent detatchment of surface lignads on QD, cuasing irreversible fluorescnece quenching.